1 files changed, 61 insertions, 23 deletions

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 886c5be14906..b79b00042310 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -449,6 +449,8 @@ static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
         ifp = ipv6_get_ifaddr(solicited_addr, dev, 1);
         if (ifp) {
                 src_addr = solicited_addr;
+                if (ifp->flags & IFA_F_OPTIMISTIC)
+                        override = 0;
                 in6_ifa_put(ifp);
         } else {
                 if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
@@ -544,7 +546,8 @@ void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
         int send_llinfo;
 
         if (saddr == NULL) {
-                if (ipv6_get_lladdr(dev, &addr_buf))
+                if (ipv6_get_lladdr(dev, &addr_buf,
+                                   (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
                         return;
                 saddr = &addr_buf;
         }
@@ -624,9 +627,33 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
         struct sk_buff *skb;
         struct icmp6hdr *hdr;
         __u8 * opt;
+        struct inet6_ifaddr *ifp;
+        int send_sllao = dev->addr_len;
         int len;
         int err;
 
+
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+        /*
+         * According to section 2.2 of RFC 4429, we must not
+         * send router solicitations with a sllao from
+         * optimistic addresses, but we may send the solicitation
+         * if we don't include the sllao.  So here we check
+         * if our address is optimistic, and if so, we
+         * supress the inclusion of the sllao.
+         */
+        if (send_sllao) {
+                ifp = ipv6_get_ifaddr(saddr, dev, 1);
+                if (ifp) {
+                        if (ifp->flags & IFA_F_OPTIMISTIC)  {
+                                send_sllao=0;
+                                in6_ifa_put(ifp);
+                        }
+                } else {
+                        send_sllao = 0;
+                }
+        }
+#endif
         ndisc_flow_init(&fl, NDISC_ROUTER_SOLICITATION, saddr, daddr,
                         dev->ifindex);
 
@@ -639,7 +666,7 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
                 return;
 
         len = sizeof(struct icmp6hdr);
-        if (dev->addr_len)
+        if (send_sllao)
                 len += ndisc_opt_addr_space(dev);
 
         skb = sock_alloc_send_skb(sk,
@@ -666,7 +693,7 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
 
         opt = (u8*) (hdr + 1);
 
-        if (dev->addr_len)
+        if (send_sllao)
                 ndisc_fill_addr_option(opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
                                        dev->addr_len, dev->type);
 
@@ -798,28 +825,39 @@ static void ndisc_recv_ns(struct sk_buff *skb)
         inc = ipv6_addr_is_multicast(daddr);
 
         if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) {
-                if (ifp->flags & IFA_F_TENTATIVE) {
-                        /* Address is tentative. If the source
-                           is unspecified address, it is someone
-                           does DAD, otherwise we ignore solicitations
-                           until DAD timer expires.
-                         */
-                        if (!dad)
+
+                if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
+                        if (dad) {
+                                if (dev->type == ARPHRD_IEEE802_TR) {
+                                        unsigned char *sadr = skb->mac.raw;
+                                        if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
+                                            sadr[9] == dev->dev_addr[1] &&
+                                            sadr[10] == dev->dev_addr[2] &&
+                                            sadr[11] == dev->dev_addr[3] &&
+                                            sadr[12] == dev->dev_addr[4] &&
+                                            sadr[13] == dev->dev_addr[5]) {
+                                                /* looped-back to us */
+                                                goto out;
+                                        }
+                                }
+
+                                /*
+                                 * We are colliding with another node
+                                 * who is doing DAD
+                                 * so fail our DAD process
+                                 */
+                                addrconf_dad_failure(ifp);
                                 goto out;
-                        if (dev->type == ARPHRD_IEEE802_TR) {
-                                unsigned char *sadr = skb->mac.raw;
-                                if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
-                                    sadr[9] == dev->dev_addr[1] &&
-                                    sadr[10] == dev->dev_addr[2] &&
-                                    sadr[11] == dev->dev_addr[3] &&
-                                    sadr[12] == dev->dev_addr[4] &&
-                                    sadr[13] == dev->dev_addr[5]) {
-                                        /* looped-back to us */
+                        } else {
+                                /*
+                                 * This is not a dad solicitation.
+                                 * If we are an optimistic node,
+                                 * we should respond.
+                                 * Otherwise, we should ignore it.
+                                 */
+                                if (!(ifp->flags & IFA_F_OPTIMISTIC))
                                         goto out;
-                                }
                         }
-                        addrconf_dad_failure(ifp);
-                        return;
                 }
 
                 idev = ifp->idev;
@@ -1408,7 +1446,7 @@ void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
 
         dev = skb->dev;
 
-        if (ipv6_get_lladdr(dev, &saddr_buf)) {
+        if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
                 ND_PRINTK2(KERN_WARNING
                            "ICMPv6 Redirect: no link-local address on %s\n",
                            dev->name);